大地电磁测深在西安凹陷基底探测中的应用

Application in the detection of basement of magnetotelluric sounding in Xi'an sag

为了研究西安凹陷深部地层及基底构造特征,采用大地电磁测深十字剖面法对西安凹陷的电性结构进行定性分析,并使用非线性共轭梯度(NLCG)二维反演方法结合地震勘探结果对其定量解释,划分出西安凹陷的主要地层及埋深.大地电磁测深反演结果与地震勘探解释结果相吻合,有效反映了西安凹陷深部地层结构的真实形态,为研究西安凹陷基底结构特征提供有效的依据.

In order to study the deep strata and structure characteristics of the basement, Xi＇an sag of magnetotelluric sounding cross section method is used to qualitative analysis of the electrical structure of Xi＇an sag, and using nonlinear conjugate gradient（ NLCG） 2 d inversion method combined with the results of the seismic exploration,the quantitative interpretation,differentiate the main formation and buried depth of Xi＇an sag. Magnetotelluric sounding inversion result is consistent with the results of seismic interpretation, effectively reflect the true form of deep strata structure,Xi＇an sag basal structure characteristics for the study of Xi＇an sag to provide effective basis.